Air control means for oil burners



S p 1940- L. I... ZFINNIGAN 2,214,246

; AIR cou'rnoL MEANS ma on. auauaas Filed Feb. 20. 1937 INV'NTOR I Annie/2x45121240):

BY W I ATTORNEY 1 Patented Sept. 10, 1940 UNITED STATES PATE 3 Claims.

This invention relates to air control means for oil burners and the primary object of this invention is to provide simple and efficient means for completely controlling the supply of air to an 5 oil burner so that maximum efficiency as respects the air conditions in the burner is obtained. Another object of the invention is to provide efficient air shutter'means in connection with an air inlet-to a fan or blower, which air shutter means is adapted to regulate the amount of air admitted to the fan when the fan is in operation and further adapted to close the inlet to the fan when the said fan is not in operation, thereby preventing a gravity circulation of cold air through the heating plant with which an oil burner is connected when the oil burner is not operating. Another object of the invention is to provide shutter means of this nature which will always close against a gravity circulation of air but will open with very slight resistance when subjected to the forced circulation produced by a driven fan.

Another object of the invention is to provide.

tube and is adjustable to vary the amount of such whirl or rotary movement, thus making it possible to direct the rotating air into the oil spray in the most eflicientmanner and at the same time making it possible to vary the distance- Other and more specific objects of this inven tion will be apparent from the following description taken in connection with the accompanying drawing.

In the drawing Figure 1 is a View in horizontal section of oil burner air control means constructed in accordance with this invention.

Fig. 2 is a vertical sectional view substantially on broken line 2--2 of Fig. 1, showing the air shutter means used in connection withthe fan inlet, the fan being omitted.

Fig. 3 is a fragmentary view in vertical section substantially on broken line 33 of Fig. 1, showing the turbulence control means.

Like reference numerals designate throughout the several views.

Referring to the drawing 5 designates a fan like parts bustion takes .place, thus preventing overheatinghousing withinwhich is mounted a fan 6 of the type used for supplying air to oil burners. An air inlet conduit 1 is positioned adjacent one end of the fan 6 substantially co-axially with said fan and provided with a convergent end portion 8 through which air is drawn by suction to the fan. The outer end of the air inlet conduit preferably has ascreened air inlet opening 9. Two'shutter members l0 and H are positioned one above another and pivotally mounted within the air inlet conduit 1 for swinging movement on horizontal axes. members are parallel and horizontal and posi tioned one above another. The shutter members l0 and II are preferably flat plates. If, the air Y inlet conduit I is cylindrical then the shutter members 10 and II are preferably rounded on their non-pivoted ends, as shown in Fig. 1. These shutter members l0 and l I are positioned so that their straight edges are substantially horizontal and parallel and substantially midway between the top and bottom of the conduit 1. In Fig. 2

these shutter members are shown in closed position. .Obviously suction of the fan 6 will move these shutter members toward each other opening air passageways between thev edges of these; shutter-members and the walls oi thefair inlet conduit 1. The twov shutter members are opera-j tively connected with 'each other by two enmeshed gear segments 13 which are coaxial with the pivots I2. 7 connection by which the weights of the two shutters, if said weights-were equaland-equallydistributed, would be substantially balanced as respects each other and'the torque, due to gravity,

NT OFFICE"! The pivots 12 for these shutter The gear segments l3 provide a exerted by one shutter member-would -alway s substantially offset thetorque; due to gravity, exerted' by the other shutter member. However, to provide for the closing of said shutter members whenthe'fan 6 is stopped, and no forced draft or suction is being exerted on said'shutter members,

I preferably make the 'lower, shutter member heavier than the upp'er'shutte'r .member. This difference in weight is just enough to cause the shutter members to over'come any pressure which may be produced by a gravity circulation of the air and move to a closed position as soon as the fan is stopped. This provides for automatically shutting offall gravity circulation of cold air through the fan housing into the heating plant when the fan is not operating. A stop member I4 adjustable by screw means I5, is provided for limiting the opening movement of the shutters l0 and II. area of the opening through which air passes'to This makes it possible to vary the v conduit [6 is provided with a semi-cylindrical I outer end portion 29. A blast tube I1 is positioned at right angles to this air delivery conduit ous angular positions.

positioned within the air delivery conduit |6..

and communicates with the semi-cylindrical outer end portion thereof through'an openinglfl. The outer end portion of the blast tube I1 is I provided with aconvergently tapered portion 20.

A pipe 2| of an oil burner is positioned substantially. axially of the blast tube l1 and an oil ato'inizing nozzle 22 is provided on the end of the pipe 2|, preferably at substantially the location of the convergent portion 20 of the blast tube. The pipe 2| extends transversely through the air delivery conduit l6 axially of the curved or semicircular end portion 29 and is connected, external to the conduit l6, with means 23' by which a supply of oil for combustion [purposes is controlled. .The turbulence control means comprises a semi-cylindrical shell 24, positioned within the rounded end portion 29 of the air delivery conduit l and movable rotatively therein into vari- A deflector plate 25 is One end of the deflector plate 25 rests on the bottom of the air delivery conduit I6 and the other end of said deflector plate 25 is connected by. pivot means 26 with one edge portion of the semi-cylindrical shell 24. A- stud bolt 21 is secured to the shell 24 and extends outwardly through a slot 28 in the semi-cylindrical end 29 of the air delivery conduit l6; providing means whereby the shell 24 may be rotatively adjusted. A wing nut 30 is provided on the stud bolt 21 to lock the-shell 24 in any desired adjusted position. I

Adjusting the shell 24 rotatively raises or lowers the pivoted end portion of 'the deflector plate 25 and him doing varies the in'cline'of saiddeflector plate. The position of this deflector plate 25 determines the direction of flow of the major portion of the air moving toward the-blast tube.

' By raising the pivoted end portion of the deflector plate 25 the main body of air is caused to take a more tangential'path as-respects the curved end portion 129 and shell 24. and a more rapid and violent whirl is imparted to this body of air as it moves' spirally toward the blast tube I1. I

Also the raising of the pivoted end of the deflector plate 25 restricts the area of the opening between I the pivoted endportion of said defiectorplate 25 and the top wall of the conduit l6, thus increasingthe velocity of this air at the same time that its rotary motion is increased and providing greater turbulence. Lowering the pivoted end portionof the deflector plate 25 permits the main body. of air to move in a less tangential direction and more nearlytoward the axis of the semicylindrical end portion 29 of the shell 15, thus imparting less whirling movement to the main bodyof air and at the same time providing a portion of the-deflector plate and the top wall of greater area of opening between the pivoted end the housing. and reducing the velocity of the air. This) reduces the turbulence of the air 'at the point of discharge. The deflector plate 25 does not control or substantially vary the amount of air supplied to the oil burner, the amount of air being determined by the capacity of the fan 6 and the adjustment of the shutter members ill and II. The discharge head developed by the fan 6 is sufficient to overcome any restriction of area that is brought about by any particular adjustmerit of the deector plate 25 necessary to obtain the desired turbulence or whirl.

Experience has shown that, if a whirling motion. is imparted to a body of air which is being directed outwardly around an atomized jet of "oil, a more intimatemixing of the air and oil is obtained and better combustion results. By governing or controlling the rate or violence of this whirl it is possible to secure the best results for different conditions and installations. Also, by varying the whirling motion imparted to this air, it is possible to vary the distance from the end of the atomizer 22 and convergent end 20 of the blast tube at which combustion takes place. This makes it possible to keep the point of combustion far enough away from the end of the blast tube, atomizer nozzle and electrodes to prevent fouling and overheating of these parts. Variations in the angle of inclination of the end of the blast tube affect the whirl required to secure the most eflicient results.

.The whirling motion of the air is created entirely by the deflector plate 25 and the semi-cyl indrical parts 29 and 24 and the interior of the blast tube is unobstructed. The whirl of the air reduces the air pressure at the location of the atomizing nozzle 22 so that at this location there is not sufiicient air to support combustion immediately adjacent the nozzle. This makes it possible to position the flame at any desired distance from the nozzle 22, as hereinbefore set forth.

The foregoing description and accompanying drawing clearly set forth what I now regard as a prefer-red embodiment of my invention but it will be understood that this disclosure is merely illustrative and that such changes in the device may be made as are. within the scope and spirit of the following claims.

I claim:

1.- In an oil burner,,a cylindrical blast tube; a convergent discharge end portion on said blast tube; oil discharge nozzle means positioned to discharge atomized oil substantially centrally of said convergent. discharge end portion of said blast tube; an oil supply pipe connected with said nozzle means; an air delivery conduit for air under pressure positioned at substantially right angles to said blast tube and communicating therewith; semi-cylindrical wall means at the end ,of said air delivery conduit in registration with duit and positionedat substantially right angles to said air delivery conduit; a convergent discharge end portion on said blast tube; oil discharge nozzle means positioned" to discharge atomized .oil substantiallycentrally of said convergent discharge end portion of said blast tube;

an oil supply pipe connected with said nozzle means; an inclined deflector plate in said air delivery conduit positioned to direct air substantially tangentially into said semi-cylindrical end portion of said air delivery conduit; and means for changing the inclination of said inclined defiector plate.

3. In an oil burner, an air delivery conduit for air under pressure, said air delivery conduit having a semi-cylindrical end portion; an oil burner blast tube communicating with the semi-cylindrical end portion of said air delivery conduit and positioned at substantially right angles to said air delivery conduit; a convergent discharge end portion on said blast tube; oil discharge nozzle means positioned to discharge atomized oil substantially centrally of said convergent discharge end portion of said blast tube; an oil supply pipe connected with said nozzle means; a. semi-cylindrical shell member rotatively mounted in the semi-cylindrical end portion of said air delivery conduit coaxially of said blast tube; means supporting said semi-cylindrical shell member in adjusted angular positions; and am inclined deflector plate having one end portion positioned on the bottom of said air delivery conduit and the other end portion pivotally con nected with one edge of said semi-cylindrical shell member and adjustable vertically by rotative adjustment of said shell member, said deflector plate directing air tangentially into the semi-cylindrical end portio'nof said air delivery conduit and imparting a whirl to the air entering said blast tube.

LAWRENCE L. FINNIGAN. 

